
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>

#if (NGX_HTTP_V2 && T_NGX_HTTP2_SRV_ENABLE)
#include <ngx_http_v2_module.h>
#endif


static void                ngx_http_wait_request_handler(ngx_event_t *ev);
static ngx_http_request_t *ngx_http_alloc_request(ngx_connection_t *c);
static void                ngx_http_process_request_line(ngx_event_t *rev);
static void                ngx_http_process_request_headers(ngx_event_t *rev);
static ssize_t             ngx_http_read_request_header(ngx_http_request_t *r);
static ngx_int_t ngx_http_alloc_large_header_buffer(ngx_http_request_t *r,
                                                    ngx_uint_t request_line);

static ngx_int_t ngx_http_process_header_line(ngx_http_request_t *r,
                                              ngx_table_elt_t    *h,
                                              ngx_uint_t          offset);
static ngx_int_t ngx_http_process_unique_header_line(ngx_http_request_t *r,
                                                     ngx_table_elt_t    *h,
                                                     ngx_uint_t offset);
static ngx_int_t ngx_http_process_multi_header_lines(ngx_http_request_t *r,
                                                     ngx_table_elt_t    *h,
                                                     ngx_uint_t offset);
static ngx_int_t ngx_http_process_host(ngx_http_request_t *r,
                                       ngx_table_elt_t *h, ngx_uint_t offset);
static ngx_int_t ngx_http_process_connection(ngx_http_request_t *r,
                                             ngx_table_elt_t    *h,
                                             ngx_uint_t          offset);
static ngx_int_t ngx_http_process_user_agent(ngx_http_request_t *r,
                                             ngx_table_elt_t    *h,
                                             ngx_uint_t          offset);

static ngx_int_t ngx_http_validate_host(ngx_str_t *host, ngx_pool_t *pool,
                                        ngx_uint_t alloc);
static ngx_int_t ngx_http_set_virtual_server(ngx_http_request_t *r,
                                             ngx_str_t          *host);
static ngx_int_t ngx_http_find_virtual_server(
    ngx_connection_t *c, ngx_http_virtual_names_t *virtual_names,
    ngx_str_t *host, ngx_http_request_t *r, ngx_http_core_srv_conf_t **cscfp);

static void ngx_http_request_handler(ngx_event_t *ev);
static void ngx_http_terminate_request(ngx_http_request_t *r, ngx_int_t rc);
static void ngx_http_terminate_handler(ngx_http_request_t *r);
static void ngx_http_finalize_connection(ngx_http_request_t *r);
static ngx_int_t ngx_http_set_write_handler(ngx_http_request_t *r);
static void      ngx_http_writer(ngx_http_request_t *r);
static void      ngx_http_request_finalizer(ngx_http_request_t *r);

static void      ngx_http_set_keepalive(ngx_http_request_t *r);
static void      ngx_http_keepalive_handler(ngx_event_t *ev);
static void      ngx_http_set_lingering_close(ngx_http_request_t *r);
static void      ngx_http_lingering_close_handler(ngx_event_t *ev);
static ngx_int_t ngx_http_post_action(ngx_http_request_t *r);
static void      ngx_http_close_request(ngx_http_request_t *r, ngx_int_t error);
static void      ngx_http_log_request(ngx_http_request_t *r);

static u_char *ngx_http_log_error(ngx_log_t *log, u_char *buf, size_t len);
static u_char *ngx_http_log_error_handler(ngx_http_request_t *r,
                                          ngx_http_request_t *sr, u_char *buf,
                                          size_t len);

#if (NGX_HTTP_SSL)
static void ngx_http_ssl_handshake(ngx_event_t *rev);
static void ngx_http_ssl_handshake_handler(ngx_connection_t *c);
#endif


static char *ngx_http_client_errors[] = {

    /* NGX_HTTP_PARSE_INVALID_METHOD */
    "client sent invalid method",

    /* NGX_HTTP_PARSE_INVALID_REQUEST */
    "client sent invalid request",

    /* NGX_HTTP_PARSE_INVALID_VERSION */
    "client sent invalid version",

    /* NGX_HTTP_PARSE_INVALID_09_METHOD */
    "client sent invalid method in HTTP/0.9 request"};


ngx_http_header_t ngx_http_headers_in[] = {
    {ngx_string("Host"), offsetof(ngx_http_headers_in_t, host),
     ngx_http_process_host},

    {ngx_string("Connection"), offsetof(ngx_http_headers_in_t, connection),
     ngx_http_process_connection},

    {ngx_string("If-Modified-Since"),
     offsetof(ngx_http_headers_in_t, if_modified_since),
     ngx_http_process_unique_header_line},

    {ngx_string("If-Unmodified-Since"),
     offsetof(ngx_http_headers_in_t, if_unmodified_since),
     ngx_http_process_unique_header_line},

    {ngx_string("If-Match"), offsetof(ngx_http_headers_in_t, if_match),
     ngx_http_process_unique_header_line},

    {ngx_string("If-None-Match"),
     offsetof(ngx_http_headers_in_t, if_none_match),
     ngx_http_process_unique_header_line},

    {ngx_string("User-Agent"), offsetof(ngx_http_headers_in_t, user_agent),
     ngx_http_process_user_agent},

    {ngx_string("Referer"), offsetof(ngx_http_headers_in_t, referer),
     ngx_http_process_header_line},

    {ngx_string("Content-Length"),
     offsetof(ngx_http_headers_in_t, content_length),
     ngx_http_process_unique_header_line},

    {ngx_string("Content-Range"),
     offsetof(ngx_http_headers_in_t, content_range),
     ngx_http_process_unique_header_line},

    {ngx_string("Content-Type"), offsetof(ngx_http_headers_in_t, content_type),
     ngx_http_process_header_line},

    {ngx_string("Range"), offsetof(ngx_http_headers_in_t, range),
     ngx_http_process_header_line},

    {ngx_string("If-Range"), offsetof(ngx_http_headers_in_t, if_range),
     ngx_http_process_unique_header_line},

    {ngx_string("Transfer-Encoding"),
     offsetof(ngx_http_headers_in_t, transfer_encoding),
     ngx_http_process_unique_header_line},

    {ngx_string("TE"), offsetof(ngx_http_headers_in_t, te),
     ngx_http_process_header_line},

    {ngx_string("Expect"), offsetof(ngx_http_headers_in_t, expect),
     ngx_http_process_unique_header_line},

    {ngx_string("Upgrade"), offsetof(ngx_http_headers_in_t, upgrade),
     ngx_http_process_header_line},

#if (NGX_HTTP_GZIP || NGX_HTTP_HEADERS)
    {ngx_string("Accept-Encoding"),
     offsetof(ngx_http_headers_in_t, accept_encoding),
     ngx_http_process_header_line},

    {ngx_string("Via"), offsetof(ngx_http_headers_in_t, via),
     ngx_http_process_header_line},
#endif

    {ngx_string("Authorization"),
     offsetof(ngx_http_headers_in_t, authorization),
     ngx_http_process_unique_header_line},

    {ngx_string("Keep-Alive"), offsetof(ngx_http_headers_in_t, keep_alive),
     ngx_http_process_header_line},

#if (NGX_HTTP_X_FORWARDED_FOR)
    {ngx_string("X-Forwarded-For"),
     offsetof(ngx_http_headers_in_t, x_forwarded_for),
     ngx_http_process_multi_header_lines},
#endif

#if (NGX_HTTP_REALIP)
    {ngx_string("X-Real-IP"), offsetof(ngx_http_headers_in_t, x_real_ip),
     ngx_http_process_header_line},
#endif

#if (NGX_HTTP_HEADERS)
    {ngx_string("Accept"), offsetof(ngx_http_headers_in_t, accept),
     ngx_http_process_header_line},

    {ngx_string("Accept-Language"),
     offsetof(ngx_http_headers_in_t, accept_language),
     ngx_http_process_header_line},
#endif

#if (NGX_HTTP_DAV)
    {ngx_string("Depth"), offsetof(ngx_http_headers_in_t, depth),
     ngx_http_process_header_line},

    {ngx_string("Destination"), offsetof(ngx_http_headers_in_t, destination),
     ngx_http_process_header_line},

    {ngx_string("Overwrite"), offsetof(ngx_http_headers_in_t, overwrite),
     ngx_http_process_header_line},

    {ngx_string("Date"), offsetof(ngx_http_headers_in_t, date),
     ngx_http_process_header_line},
#endif

    {ngx_string("Cookie"), offsetof(ngx_http_headers_in_t, cookies),
     ngx_http_process_multi_header_lines},

#if (NGX_HTTP_PROXY_CONNECT)

    {ngx_string("Proxy-Authorization"),
     offsetof(ngx_http_headers_in_t, proxy_authorization),
     ngx_http_process_header_line},

#endif

    {ngx_null_string, 0, NULL}};


void
ngx_http_init_connection(ngx_connection_t *c)
{
    ngx_uint_t             i;
    ngx_event_t           *rev;
    struct sockaddr_in    *sin;
    ngx_http_port_t       *port;
    ngx_http_in_addr_t    *addr;
    ngx_http_log_ctx_t    *ctx;
    ngx_http_connection_t *hc;
#if (NGX_HAVE_INET6)
    struct sockaddr_in6 *sin6;
    ngx_http_in6_addr_t *addr6;
#endif
#if (NGX_HTTP_V2 && T_NGX_HTTP2_SRV_ENABLE)
    ngx_http_v2_srv_conf_t *h2scf;
#endif


    hc = ngx_pcalloc(c->pool, sizeof(ngx_http_connection_t));
    if (hc == NULL)
    {
        ngx_http_close_connection(c);
        return;
    }

    c->data = hc;

    /* find the server configuration for the address:port */

    port = c->listening->servers;

    if (port->naddrs > 1)
    {
        /*
         * there are several addresses on this port and one of them
         * is an "*:port" wildcard so getsockname() in ngx_http_server_addr()
         * is required to determine a server address
         */

        if (ngx_connection_local_sockaddr(c, NULL, 0) != NGX_OK)
        {
            ngx_http_close_connection(c);
            return;
        }

        switch (c->local_sockaddr->sa_family)
        {
#if (NGX_HAVE_INET6)
        case AF_INET6:
            sin6 = (struct sockaddr_in6 *)c->local_sockaddr;

            addr6 = port->addrs;

            /* the last address is "*" */

            for (i = 0; i < port->naddrs - 1; i++)
            {
                if (ngx_memcmp(&addr6[i].addr6, &sin6->sin6_addr, 16) == 0)
                {
                    break;
                }
            }

            hc->addr_conf = &addr6[i].conf;

            break;
#endif

        default: /* AF_INET */
            sin = (struct sockaddr_in *)c->local_sockaddr;

            addr = port->addrs;

            /* the last address is "*" */

            for (i = 0; i < port->naddrs - 1; i++)
            {
                if (addr[i].addr == sin->sin_addr.s_addr)
                {
                    break;
                }
            }

            hc->addr_conf = &addr[i].conf;

            break;
        }
    }
    else
    {
        switch (c->local_sockaddr->sa_family)
        {
#if (NGX_HAVE_INET6)
        case AF_INET6:
            addr6         = port->addrs;
            hc->addr_conf = &addr6[0].conf;
            break;
#endif

        default: /* AF_INET */
            addr          = port->addrs;
            hc->addr_conf = &addr[0].conf;
            break;
        }
    }

    /* the default server configuration for the address:port */
    hc->conf_ctx = hc->addr_conf->default_server->ctx;

    ctx = ngx_palloc(c->pool, sizeof(ngx_http_log_ctx_t));
    if (ctx == NULL)
    {
        ngx_http_close_connection(c);
        return;
    }

    ctx->connection      = c;
    ctx->request         = NULL;
    ctx->current_request = NULL;

    c->log->connection = c->number;
    c->log->handler    = ngx_http_log_error;
    c->log->data       = ctx;
    c->log->action     = "waiting for request";

    c->log_error = NGX_ERROR_INFO;

    rev               = c->read;
    rev->handler      = ngx_http_wait_request_handler;
    c->write->handler = ngx_http_empty_handler;

#if (NGX_HTTP_V2 && T_NGX_HTTP2_SRV_ENABLE)
    h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module);
#endif

#if (NGX_HTTP_V2)
    if (
#if (T_NGX_HTTP2_SRV_ENABLE)
        (
#endif
            hc->addr_conf->http2
#if (T_NGX_HTTP2_SRV_ENABLE)
            && h2scf->enable != 0)
        || h2scf->enable == 1
#endif
    )
    {
        rev->handler = ngx_http_v2_init;
    }
#endif

#if (NGX_HTTP_SSL)
    {
        ngx_http_ssl_srv_conf_t *sscf;

        sscf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_ssl_module);

        if (sscf->enable || hc->addr_conf->ssl)
        {
            hc->ssl        = 1;
            c->log->action = "SSL handshaking";
            rev->handler   = ngx_http_ssl_handshake;
        }
    }
#endif

    if (hc->addr_conf->proxy_protocol)
    {
        hc->proxy_protocol = 1;
        c->log->action     = "reading PROXY protocol";
    }

    if (rev->ready)
    {
        /* the deferred accept(), iocp */

        if (ngx_use_accept_mutex)
        {
            ngx_post_event(rev, &ngx_posted_events);
            return;
        }

        rev->handler(rev);
        return;
    }

    ngx_add_timer(rev, c->listening->post_accept_timeout);
    ngx_reusable_connection(c, 1);

    if (ngx_handle_read_event(rev, 0) != NGX_OK)
    {
        ngx_http_close_connection(c);
        return;
    }
}


static void
ngx_http_wait_request_handler(ngx_event_t *rev)
{
    u_char                   *p;
    size_t                    size;
    ssize_t                   n;
    ngx_buf_t                *b;
    ngx_connection_t         *c;
    ngx_http_connection_t    *hc;
    ngx_http_core_srv_conf_t *cscf;

    c = rev->data;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http wait request handler");

    if (rev->timedout)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
        ngx_http_close_connection(c);
        return;
    }

    if (c->close)
    {
        ngx_http_close_connection(c);
        return;
    }

    hc   = c->data;
    cscf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_core_module);

    size = cscf->client_header_buffer_size;

    b = c->buffer;

    if (b == NULL)
    {
        b = ngx_create_temp_buf(c->pool, size);
        if (b == NULL)
        {
            ngx_http_close_connection(c);
            return;
        }

        c->buffer = b;
    }
    else if (b->start == NULL)
    {
        b->start = ngx_palloc(c->pool, size);
        if (b->start == NULL)
        {
            ngx_http_close_connection(c);
            return;
        }

        b->pos  = b->start;
        b->last = b->start;
        b->end  = b->last + size;
    }

    n = c->recv(c, b->last, size);

    if (n == NGX_AGAIN)
    {
        if (!rev->timer_set)
        {
            ngx_add_timer(rev, c->listening->post_accept_timeout);
            ngx_reusable_connection(c, 1);
        }

        if (ngx_handle_read_event(rev, 0) != NGX_OK)
        {
            ngx_http_close_connection(c);
            return;
        }

        /*
         * We are trying to not hold c->buffer's memory for an idle connection.
         */

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        /* For the Async implementation we need the same buffer to be used
         * again on any async calls that have not completed.
         * As such we need to turn off this optimisation if an async request
         * is still in progress.
         */
        if ((c->async_enable && !ngx_ssl_waiting_for_async(c))
            || !c->async_enable)
        {
#endif
            if (ngx_pfree(c->pool, b->start) == NGX_OK)
            {
                b->start = NULL;
            }
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        }
#endif

        return;
    }

    if (n == NGX_ERROR)
    {
        ngx_http_close_connection(c);
        return;
    }

    if (n == 0)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, 0, "client closed connection");
        ngx_http_close_connection(c);
        return;
    }

    b->last += n;
#if (T_NGX_REQ_STATUS)
    c->received += n;
#endif

    if (hc->proxy_protocol)
    {
        hc->proxy_protocol = 0;

        p = ngx_proxy_protocol_read(c, b->pos, b->last);

        if (p == NULL)
        {
            ngx_http_close_connection(c);
            return;
        }

        b->pos = p;

        if (b->pos == b->last)
        {
            c->log->action = "waiting for request";
            b->pos         = b->start;
            b->last        = b->start;
            ngx_post_event(rev, &ngx_posted_events);
            return;
        }
    }

    c->log->action = "reading client request line";

    ngx_reusable_connection(c, 0);

    c->data = ngx_http_create_request(c);
    if (c->data == NULL)
    {
        ngx_http_close_connection(c);
        return;
    }

    rev->handler = ngx_http_process_request_line;
    ngx_http_process_request_line(rev);
}


ngx_http_request_t *
ngx_http_create_request(ngx_connection_t *c)
{
    ngx_http_request_t       *r;
    ngx_http_log_ctx_t       *ctx;
    ngx_http_core_loc_conf_t *clcf;

    r = ngx_http_alloc_request(c);
    if (r == NULL)
    {
        return NULL;
    }

    c->requests++;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    ngx_set_connection_log(c, clcf->error_log);

    ctx                  = c->log->data;
    ctx->request         = r;
    ctx->current_request = r;

#if (NGX_STAT_STUB)
    (void)ngx_atomic_fetch_add(ngx_stat_reading, 1);
    r->stat_reading = 1;
    (void)ngx_atomic_fetch_add(ngx_stat_requests, 1);
#endif

    return r;
}


static ngx_http_request_t *
ngx_http_alloc_request(ngx_connection_t *c)
{
    ngx_pool_t                *pool;
    ngx_time_t                *tp;
    ngx_http_request_t        *r;
    ngx_http_connection_t     *hc;
    ngx_http_core_srv_conf_t  *cscf;
    ngx_http_core_main_conf_t *cmcf;

    hc = c->data;

    cscf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_core_module);

    pool = ngx_create_pool(cscf->request_pool_size, c->log);
    if (pool == NULL)
    {
        return NULL;
    }

    r = ngx_pcalloc(pool, sizeof(ngx_http_request_t));
    if (r == NULL)
    {
        ngx_destroy_pool(pool);
        return NULL;
    }

    r->pool = pool;

    r->http_connection = hc;
    r->signature       = NGX_HTTP_MODULE;
    r->connection      = c;

    r->main_conf = hc->conf_ctx->main_conf;
    r->srv_conf  = hc->conf_ctx->srv_conf;
    r->loc_conf  = hc->conf_ctx->loc_conf;

    r->read_event_handler = ngx_http_block_reading;

    r->header_in = hc->busy ? hc->busy->buf : c->buffer;

    if (ngx_list_init(&r->headers_out.headers, r->pool, 20,
                      sizeof(ngx_table_elt_t))
        != NGX_OK)
    {
        ngx_destroy_pool(r->pool);
        return NULL;
    }

    if (ngx_list_init(&r->headers_out.trailers, r->pool, 4,
                      sizeof(ngx_table_elt_t))
        != NGX_OK)
    {
        ngx_destroy_pool(r->pool);
        return NULL;
    }

    r->ctx = ngx_pcalloc(r->pool, sizeof(void *) * ngx_http_max_module);
    if (r->ctx == NULL)
    {
        ngx_destroy_pool(r->pool);
        return NULL;
    }

    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);

    r->variables = ngx_pcalloc(
        r->pool, cmcf->variables.nelts * sizeof(ngx_http_variable_value_t));
    if (r->variables == NULL)
    {
        ngx_destroy_pool(r->pool);
        return NULL;
    }

#if (NGX_HTTP_SSL)
    if (c->ssl)
    {
        r->main_filter_need_in_memory = 1;
    }
#endif

    r->main  = r;
    r->count = 1;

#if (T_NGX_RET_CACHE)
    {
        struct timeval            tv;
        ngx_http_core_loc_conf_t *clcf;

        clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

        if (clcf->request_time_cache)
        {
            tp            = ngx_timeofday();
            r->start_sec  = tp->sec;
            r->start_msec = tp->msec;
            r->start_usec = tp->usec;
        }
        else
        {
            ngx_gettimeofday(&tv);
            r->start_sec  = tv.tv_sec;
            r->start_msec = tv.tv_usec / 1000;
            r->start_usec = tv.tv_usec % 1000;
        }
    }
#else
    tp            = ngx_timeofday();
    r->start_sec  = tp->sec;
    r->start_msec = tp->msec;
#endif

    r->method       = NGX_HTTP_UNKNOWN;
    r->http_version = NGX_HTTP_VERSION_10;

    r->headers_in.content_length_n    = -1;
    r->headers_in.keep_alive_n        = -1;
    r->headers_out.content_length_n   = -1;
    r->headers_out.last_modified_time = -1;

    r->uri_changes = NGX_HTTP_MAX_URI_CHANGES + 1;
    r->subrequests = NGX_HTTP_MAX_SUBREQUESTS + 1;

    r->http_state = NGX_HTTP_READING_REQUEST_STATE;

    r->log_handler = ngx_http_log_error_handler;

    return r;
}


#if (NGX_HTTP_SSL)

static void
ngx_http_ssl_handshake(ngx_event_t *rev)
{
    u_char                   *p, buf[NGX_PROXY_PROTOCOL_MAX_HEADER + 1];
    size_t                    size;
    ssize_t                   n;
    ngx_err_t                 err;
    ngx_int_t                 rc;
    ngx_connection_t         *c;
    ngx_http_connection_t    *hc;
    ngx_http_ssl_srv_conf_t  *sscf;
    ngx_http_core_loc_conf_t *clcf;

    c  = rev->data;
    hc = c->data;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, rev->log, 0, "http check ssl handshake");

    if (rev->timedout)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
        ngx_http_close_connection(c);
        return;
    }

    if (c->close)
    {
        ngx_http_close_connection(c);
        return;
    }

    size = hc->proxy_protocol ? sizeof(buf) : 1;

    n = recv(c->fd, (char *)buf, size, MSG_PEEK);

    err = ngx_socket_errno;

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, rev->log, 0, "http recv(): %z", n);

    if (n == -1)
    {
        if (err == NGX_EAGAIN)
        {
            rev->ready = 0;

            if (!rev->timer_set)
            {
                ngx_add_timer(rev, c->listening->post_accept_timeout);
                ngx_reusable_connection(c, 1);
            }

            if (ngx_handle_read_event(rev, 0) != NGX_OK)
            {
                ngx_http_close_connection(c);
            }

            return;
        }

        ngx_connection_error(c, err, "recv() failed");
        ngx_http_close_connection(c);

        return;
    }

    if (hc->proxy_protocol)
    {
        hc->proxy_protocol = 0;

        p = ngx_proxy_protocol_read(c, buf, buf + n);

        if (p == NULL)
        {
            ngx_http_close_connection(c);
            return;
        }

        size = p - buf;

        if (c->recv(c, buf, size) != (ssize_t)size)
        {
            ngx_http_close_connection(c);
            return;
        }

        c->log->action = "SSL handshaking";

        if (n == (ssize_t)size)
        {
            ngx_post_event(rev, &ngx_posted_events);
            return;
        }

        n      = 1;
        buf[0] = *p;
    }

    if (n == 1)
    {
        if (buf[0] & 0x80 /* SSLv2 */ || buf[0] == 0x16 /* SSLv3/TLSv1 */)
        {
            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, rev->log, 0,
                           "https ssl handshake: 0x%02Xd", buf[0]);

            clcf = ngx_http_get_module_loc_conf(hc->conf_ctx,
                                                ngx_http_core_module);

            if (clcf->tcp_nodelay && ngx_tcp_nodelay(c) != NGX_OK)
            {
                ngx_http_close_connection(c);
                return;
            }

            sscf =
                ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_ssl_module);

            if (ngx_ssl_create_connection(&sscf->ssl, c, NGX_SSL_BUFFER)
                != NGX_OK)
            {
                ngx_http_close_connection(c);
                return;
            }

#if (T_NGX_SSL_HANDSHAKE_TIME)
            {
                /* ssl handshake start time */
                ngx_time_t *tp               = ngx_timeofday();
                c->ssl->handshake_start_msec = tp->sec * 1000 + tp->msec;
            }
#endif

            ngx_reusable_connection(c, 0);
            rc = ngx_ssl_handshake(c);

            if (rc == NGX_AGAIN)
            {
                if (!rev->timer_set)
                {
                    ngx_add_timer(rev, c->listening->post_accept_timeout);
                }

                c->ssl->handler = ngx_http_ssl_handshake_handler;
                return;
            }

            ngx_http_ssl_handshake_handler(c);

            return;
        }

        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, rev->log, 0, "plain http");

        c->log->action = "waiting for request";

        rev->handler = ngx_http_wait_request_handler;
        ngx_http_wait_request_handler(rev);

        return;
    }

    ngx_log_error(NGX_LOG_INFO, c->log, 0, "client closed connection");
    ngx_http_close_connection(c);
}


static void
ngx_http_ssl_handshake_handler(ngx_connection_t *c)
{
    if (c->ssl->handshaked)
    {
        /*
         * The majority of browsers do not send the "close notify" alert.
         * Among them are MSIE, old Mozilla, Netscape 4, Konqueror,
         * and Links.  And what is more, MSIE ignores the server's alert.
         *
         * Opera and recent Mozilla send the alert.
         */

        c->ssl->no_wait_shutdown = 1;

#if (NGX_HTTP_V2                                                       \
     && (defined    TLSEXT_TYPE_application_layer_protocol_negotiation \
         || defined TLSEXT_TYPE_next_proto_neg))
        {
            unsigned int           len;
            const unsigned char   *data;
            ngx_http_connection_t *hc;

#if (T_NGX_HTTP2_SRV_ENABLE)
            ngx_http_v2_srv_conf_t *h2scf;
#endif
            hc = c->data;

#if (T_NGX_HTTP2_SRV_ENABLE)
            h2scf =
                ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module);
#endif

            if (
#if (T_NGX_HTTP2_SRV_ENABLE)
                (
#endif
                    hc->addr_conf->http2
#if (T_NGX_HTTP2_SRV_ENABLE)
                    && h2scf->enable != 0)
                || h2scf->enable == 1
#endif
            )
            {
#ifdef TLSEXT_TYPE_application_layer_protocol_negotiation
                SSL_get0_alpn_selected(c->ssl->connection, &data, &len);

#ifdef TLSEXT_TYPE_next_proto_neg
                if (len == 0)
                {
                    SSL_get0_next_proto_negotiated(c->ssl->connection, &data,
                                                   &len);
                }
#endif

#else /* TLSEXT_TYPE_next_proto_neg */
                SSL_get0_next_proto_negotiated(c->ssl->connection, &data, &len);
#endif

                if (len == 2 && data[0] == 'h' && data[1] == '2')
                {
                    ngx_http_v2_init(c->read);
                    return;
                }
            }
        }
#endif

        c->log->action = "waiting for request";

        c->read->handler = ngx_http_wait_request_handler;
        /* STUB: epoll edge */ c->write->handler = ngx_http_empty_handler;

        ngx_reusable_connection(c, 1);

        ngx_http_wait_request_handler(c->read);

        return;
    }

    if (c->read->timedout)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
    }

    ngx_http_close_connection(c);
}


#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME

int
ngx_http_ssl_servername(ngx_ssl_conn_t *ssl_conn, int *ad, void *arg)
{
    ngx_int_t                 rc;
    ngx_str_t                 host;
    const char               *servername;
    ngx_connection_t         *c;
    ngx_http_connection_t    *hc;
    ngx_http_ssl_srv_conf_t  *sscf;
    ngx_http_core_loc_conf_t *clcf;
    ngx_http_core_srv_conf_t *cscf;

    c = ngx_ssl_get_connection(ssl_conn);

    if (c->ssl->handshaked)
    {
        *ad = SSL_AD_NO_RENEGOTIATION;
        return SSL_TLSEXT_ERR_ALERT_FATAL;
    }

    servername = SSL_get_servername(ssl_conn, TLSEXT_NAMETYPE_host_name);

    if (servername == NULL)
    {
        return SSL_TLSEXT_ERR_OK;
    }

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "SSL server name: \"%s\"",
                   servername);

    host.len = ngx_strlen(servername);

    if (host.len == 0)
    {
        return SSL_TLSEXT_ERR_OK;
    }

    host.data = (u_char *)servername;

    rc = ngx_http_validate_host(&host, c->pool, 1);

    if (rc == NGX_ERROR)
    {
        *ad = SSL_AD_INTERNAL_ERROR;
        return SSL_TLSEXT_ERR_ALERT_FATAL;
    }

    if (rc == NGX_DECLINED)
    {
        return SSL_TLSEXT_ERR_OK;
    }

    hc = c->data;

    rc = ngx_http_find_virtual_server(c, hc->addr_conf->virtual_names, &host,
                                      NULL, &cscf);

    if (rc == NGX_ERROR)
    {
        *ad = SSL_AD_INTERNAL_ERROR;
        return SSL_TLSEXT_ERR_ALERT_FATAL;
    }

    if (rc == NGX_DECLINED)
    {
        return SSL_TLSEXT_ERR_OK;
    }

    hc->ssl_servername = ngx_palloc(c->pool, sizeof(ngx_str_t));
    if (hc->ssl_servername == NULL)
    {
        *ad = SSL_AD_INTERNAL_ERROR;
        return SSL_TLSEXT_ERR_ALERT_FATAL;
    }

    *hc->ssl_servername = host;

    hc->conf_ctx = cscf->ctx;

    clcf = ngx_http_get_module_loc_conf(hc->conf_ctx, ngx_http_core_module);

    ngx_set_connection_log(c, clcf->error_log);

    sscf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_ssl_module);

    c->ssl->buffer_size = sscf->buffer_size;

    if (sscf->ssl.ctx)
    {
        SSL_set_SSL_CTX(ssl_conn, sscf->ssl.ctx);

        /*
         * SSL_set_SSL_CTX() only changes certs as of 1.0.0d
         * adjust other things we care about
         */

        SSL_set_verify(ssl_conn, SSL_CTX_get_verify_mode(sscf->ssl.ctx),
                       SSL_CTX_get_verify_callback(sscf->ssl.ctx));

        SSL_set_verify_depth(ssl_conn, SSL_CTX_get_verify_depth(sscf->ssl.ctx));

#if OPENSSL_VERSION_NUMBER >= 0x009080dfL
        /* only in 0.9.8m+ */
        SSL_clear_options(ssl_conn, SSL_get_options(ssl_conn)
                                        & ~SSL_CTX_get_options(sscf->ssl.ctx));
#endif

        SSL_set_options(ssl_conn, SSL_CTX_get_options(sscf->ssl.ctx));

#ifdef SSL_OP_NO_RENEGOTIATION
        SSL_set_options(ssl_conn, SSL_OP_NO_RENEGOTIATION);
#endif
    }

    return SSL_TLSEXT_ERR_OK;
}

#endif


#ifdef SSL_R_CERT_CB_ERROR

int
ngx_http_ssl_certificate(ngx_ssl_conn_t *ssl_conn, void *arg)
{
    ngx_str_t                 cert, key;
    ngx_uint_t                i, nelts;
    ngx_connection_t         *c;
    ngx_http_request_t       *r;
    ngx_http_ssl_srv_conf_t  *sscf;
    ngx_http_complex_value_t *certs, *keys;

    c = ngx_ssl_get_connection(ssl_conn);

    if (c->ssl->handshaked)
    {
        return 0;
    }

    r = ngx_http_alloc_request(c);
    if (r == NULL)
    {
        return 0;
    }

    r->logged = 1;

    sscf = arg;

    nelts = sscf->certificate_values->nelts;
    certs = sscf->certificate_values->elts;
    keys  = sscf->certificate_key_values->elts;

    for (i = 0; i < nelts; i++)
    {
        if (ngx_http_complex_value(r, &certs[i], &cert) != NGX_OK)
        {
            goto failed;
        }

        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "ssl cert: \"%s\"",
                       cert.data);

        if (ngx_http_complex_value(r, &keys[i], &key) != NGX_OK)
        {
            goto failed;
        }

        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "ssl key: \"%s\"",
                       key.data);

        if (ngx_ssl_connection_certificate(c, r->pool, &cert, &key,
                                           sscf->passwords)
            != NGX_OK)
        {
            goto failed;
        }
    }

    ngx_http_free_request(r, 0);
    c->destroyed = 0;
    return 1;

failed:

    ngx_http_free_request(r, 0);
    c->destroyed = 0;
    return 0;
}

#endif

#endif


static void
ngx_http_process_request_line(ngx_event_t *rev)
{
    ssize_t             n;
    ngx_int_t           rc, rv;
    ngx_str_t           host;
    ngx_connection_t   *c;
    ngx_http_request_t *r;

    c = rev->data;
    r = c->data;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, rev->log, 0,
                   "http process request line");

    if (rev->timedout)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
        c->timedout = 1;
        ngx_http_close_request(r, NGX_HTTP_REQUEST_TIME_OUT);
        return;
    }

    rc = NGX_AGAIN;

    for (;;)
    {
        if (rc == NGX_AGAIN)
        {
            n = ngx_http_read_request_header(r);

            if (n == NGX_AGAIN || n == NGX_ERROR)
            {
                break;
            }
        }

        rc = ngx_http_parse_request_line(r, r->header_in);

        if (rc == NGX_OK)
        {
            /* the request line has been parsed successfully */

            r->request_line.len  = r->request_end - r->request_start;
            r->request_line.data = r->request_start;
            r->request_length    = r->header_in->pos - r->request_start;

            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
                           "http request line: \"%V\"", &r->request_line);

            r->method_name.len  = r->method_end - r->request_start + 1;
            r->method_name.data = r->request_line.data;

            if (r->http_protocol.data)
            {
                r->http_protocol.len = r->request_end - r->http_protocol.data;
            }

            if (ngx_http_process_request_uri(r) != NGX_OK)
            {
                break;
            }

#if (NGX_HTTP_PROXY_CONNECT)

            if (r->connect_host_start && r->connect_host_end)
            {
                host.len  = r->connect_host_end - r->connect_host_start;
                host.data = r->connect_host_start;
                rc        = ngx_http_validate_host(&host, r->pool, 0);

                if (rc == NGX_DECLINED)
                {
                    ngx_log_error(NGX_LOG_INFO, c->log, 0,
                                  "client sent invalid host in request line");
                    ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                    return;
                }

                if (rc == NGX_ERROR)
                {
                    ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                    return;
                }

                r->connect_host = host;

                if (!r->connect_port_end)
                {
                    ngx_log_error(NGX_LOG_INFO, c->log, 0,
                                  "client sent no port in request line");
                    ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                    return;
                }

                r->connect_port.data = r->connect_host_end + 1;
                r->connect_port.len =
                    r->connect_port_end - r->connect_host_end - 1;

                ngx_int_t port;

                port = ngx_atoi(r->connect_port.data, r->connect_port.len);
                if (port == NGX_ERROR || port < 1 || port > 65535)
                {
                    ngx_log_error(NGX_LOG_INFO, c->log, 0,
                                  "client sent invalid port in request line");
                    ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                    return;
                }

                r->connect_port_n = port;
            }
#endif

            if (r->schema_end)
            {
                r->schema.len  = r->schema_end - r->schema_start;
                r->schema.data = r->schema_start;
            }

            if (r->host_end)
            {
                host.len  = r->host_end - r->host_start;
                host.data = r->host_start;

                rc = ngx_http_validate_host(&host, r->pool, 0);

                if (rc == NGX_DECLINED)
                {
                    ngx_log_error(NGX_LOG_INFO, c->log, 0,
                                  "client sent invalid host in request line");
                    ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                    break;
                }

                if (rc == NGX_ERROR)
                {
                    ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                    break;
                }

                if (ngx_http_set_virtual_server(r, &host) == NGX_ERROR)
                {
                    break;
                }

                r->headers_in.server = host;
            }

            if (r->http_version < NGX_HTTP_VERSION_10)
            {
                if (r->headers_in.server.len == 0
                    && ngx_http_set_virtual_server(r, &r->headers_in.server)
                           == NGX_ERROR)
                {
                    break;
                }

                ngx_http_process_request(r);
                break;
            }


            if (ngx_list_init(&r->headers_in.headers, r->pool, 20,
                              sizeof(ngx_table_elt_t))
                != NGX_OK)
            {
                ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                break;
            }

            c->log->action = "reading client request headers";

            rev->handler = ngx_http_process_request_headers;
            ngx_http_process_request_headers(rev);

            break;
        }

        if (rc != NGX_AGAIN)
        {
            /* there was error while a request line parsing */

            ngx_log_error(NGX_LOG_INFO, c->log, 0,
                          ngx_http_client_errors[rc - NGX_HTTP_CLIENT_ERROR]);

            if (rc == NGX_HTTP_PARSE_INVALID_VERSION)
            {
                ngx_http_finalize_request(r, NGX_HTTP_VERSION_NOT_SUPPORTED);
            }
            else
            {
                ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
            }

            break;
        }

        /* NGX_AGAIN: a request line parsing is still incomplete */

        if (r->header_in->pos == r->header_in->end)
        {
            rv = ngx_http_alloc_large_header_buffer(r, 1);

            if (rv == NGX_ERROR)
            {
                ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                break;
            }

            if (rv == NGX_DECLINED)
            {
                r->request_line.len  = r->header_in->end - r->request_start;
                r->request_line.data = r->request_start;

                ngx_log_error(NGX_LOG_INFO, c->log, 0,
                              "client sent too long URI");
                ngx_http_finalize_request(r, NGX_HTTP_REQUEST_URI_TOO_LARGE);
                break;
            }
        }
    }

    ngx_http_run_posted_requests(c);
}


ngx_int_t
ngx_http_process_request_uri(ngx_http_request_t *r)
{
    ngx_http_core_srv_conf_t *cscf;

    if (r->args_start)
    {
        r->uri.len = r->args_start - 1 - r->uri_start;
    }
    else
    {
        r->uri.len = r->uri_end - r->uri_start;
    }

    if (r->complex_uri || r->quoted_uri)
    {
        r->uri.data = ngx_pnalloc(r->pool, r->uri.len + 1);
        if (r->uri.data == NULL)
        {
            ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
            return NGX_ERROR;
        }

        cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

        if (ngx_http_parse_complex_uri(r, cscf->merge_slashes) != NGX_OK)
        {
            r->uri.len = 0;

            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                          "client sent invalid request");
            ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
            return NGX_ERROR;
        }
    }
    else
    {
        r->uri.data = r->uri_start;
    }

#if (T_NGX_VARS)
    if (r->args_start)
    {
        r->raw_uri.len = r->args_start - 1 - r->uri_start;
    }
    else
    {
        r->raw_uri.len = r->uri_end - r->uri_start;
    }
    r->raw_uri.data = r->uri_start;
#endif

    r->unparsed_uri.len  = r->uri_end - r->uri_start;
    r->unparsed_uri.data = r->uri_start;

    r->valid_unparsed_uri = r->space_in_uri ? 0 : 1;

    if (r->uri_ext)
    {
        if (r->args_start)
        {
            r->exten.len = r->args_start - 1 - r->uri_ext;
        }
        else
        {
            r->exten.len = r->uri_end - r->uri_ext;
        }

        r->exten.data = r->uri_ext;
    }

    if (r->args_start && r->uri_end > r->args_start)
    {
        r->args.len  = r->uri_end - r->args_start;
        r->args.data = r->args_start;
    }

#if (NGX_WIN32)
    {
        u_char *p, *last;

        p    = r->uri.data;
        last = r->uri.data + r->uri.len;

        while (p < last)
        {
            if (*p++ == ':')
            {
                /*
                 * this check covers "::$data", "::$index_allocation" and
                 * ":$i30:$index_allocation"
                 */

                if (p < last && *p == '$')
                {
                    ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                                  "client sent unsafe win32 URI");
                    ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
                    return NGX_ERROR;
                }
            }
        }

        p = r->uri.data + r->uri.len - 1;

        while (p > r->uri.data)
        {
            if (*p == ' ')
            {
                p--;
                continue;
            }

            if (*p == '.')
            {
                p--;
                continue;
            }

            break;
        }

        if (p != r->uri.data + r->uri.len - 1)
        {
            r->uri.len = p + 1 - r->uri.data;
            ngx_http_set_exten(r);
        }
    }
#endif

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http uri: \"%V\"", &r->uri);

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http args: \"%V\"", &r->args);

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http exten: \"%V\"", &r->exten);

    return NGX_OK;
}


static void
ngx_http_process_request_headers(ngx_event_t *rev)
{
    u_char                    *p;
    size_t                     len;
    ssize_t                    n;
    ngx_int_t                  rc, rv;
    ngx_table_elt_t           *h;
    ngx_connection_t          *c;
    ngx_http_header_t         *hh;
    ngx_http_request_t        *r;
    ngx_http_core_srv_conf_t  *cscf;
    ngx_http_core_main_conf_t *cmcf;

    c = rev->data;
    r = c->data;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, rev->log, 0,
                   "http process request header line");

    if (rev->timedout)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
        c->timedout = 1;
        ngx_http_close_request(r, NGX_HTTP_REQUEST_TIME_OUT);
        return;
    }

    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);

    rc = NGX_AGAIN;

    for (;;)
    {
        if (rc == NGX_AGAIN)
        {
            if (r->header_in->pos == r->header_in->end)
            {
                rv = ngx_http_alloc_large_header_buffer(r, 0);

                if (rv == NGX_ERROR)
                {
                    ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                    break;
                }

                if (rv == NGX_DECLINED)
                {
                    p = r->header_name_start;

                    r->lingering_close = 1;

                    if (p == NULL)
                    {
                        ngx_log_error(NGX_LOG_INFO, c->log, 0,
                                      "client sent too large request");
                        ngx_http_finalize_request(
                            r, NGX_HTTP_REQUEST_HEADER_TOO_LARGE);
                        break;
                    }

                    len = r->header_in->end - p;

                    if (len > NGX_MAX_ERROR_STR - 300)
                    {
                        len = NGX_MAX_ERROR_STR - 300;
                    }

                    ngx_log_error(
                        NGX_LOG_INFO, c->log, 0,
                        "client sent too long header line: \"%*s...\"", len,
                        r->header_name_start);

                    ngx_http_finalize_request(
                        r, NGX_HTTP_REQUEST_HEADER_TOO_LARGE);
                    break;
                }
            }

            n = ngx_http_read_request_header(r);

            if (n == NGX_AGAIN || n == NGX_ERROR)
            {
                break;
            }
        }

        /* the host header could change the server configuration context */
        cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

        rc = ngx_http_parse_header_line(r, r->header_in,
                                        cscf->underscores_in_headers);

        if (rc == NGX_OK)
        {
            r->request_length += r->header_in->pos - r->header_name_start;

            if (r->invalid_header && cscf->ignore_invalid_headers)
            {
                /* there was error while a header line parsing */

                ngx_log_error(NGX_LOG_INFO, c->log, 0,
                              "client sent invalid header line: \"%*s\"",
                              r->header_end - r->header_name_start,
                              r->header_name_start);
                continue;
            }

            /* a header line has been parsed successfully */

            h = ngx_list_push(&r->headers_in.headers);
            if (h == NULL)
            {
                ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                break;
            }

            h->hash = r->header_hash;

            h->key.len              = r->header_name_end - r->header_name_start;
            h->key.data             = r->header_name_start;
            h->key.data[h->key.len] = '\0';

            h->value.len                = r->header_end - r->header_start;
            h->value.data               = r->header_start;
            h->value.data[h->value.len] = '\0';

            h->lowcase_key = ngx_pnalloc(r->pool, h->key.len);
            if (h->lowcase_key == NULL)
            {
                ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                break;
            }

            if (h->key.len == r->lowcase_index)
            {
                ngx_memcpy(h->lowcase_key, r->lowcase_header, h->key.len);
            }
            else
            {
                ngx_strlow(h->lowcase_key, h->key.data, h->key.len);
            }

            hh = ngx_hash_find(&cmcf->headers_in_hash, h->hash, h->lowcase_key,
                               h->key.len);

            if (hh && hh->handler(r, h, hh->offset) != NGX_OK)
            {
                break;
            }

            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                           "http header: \"%V: %V\"", &h->key, &h->value);

            continue;
        }

        if (rc == NGX_HTTP_PARSE_HEADER_DONE)
        {
            /* a whole header has been parsed successfully */

            ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                           "http header done");

            r->request_length += r->header_in->pos - r->header_name_start;

            r->http_state = NGX_HTTP_PROCESS_REQUEST_STATE;

            rc = ngx_http_process_request_header(r);

            if (rc != NGX_OK)
            {
                break;
            }

            ngx_http_process_request(r);

            break;
        }

        if (rc == NGX_AGAIN)
        {
            /* a header line parsing is still not complete */

            continue;
        }

        /* rc == NGX_HTTP_PARSE_INVALID_HEADER */

        ngx_log_error(NGX_LOG_INFO, c->log, 0,
                      "client sent invalid header line");

        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
        break;
    }

    ngx_http_run_posted_requests(c);
}


static ssize_t
ngx_http_read_request_header(ngx_http_request_t *r)
{
    ssize_t                   n;
    ngx_event_t              *rev;
    ngx_connection_t         *c;
    ngx_http_core_srv_conf_t *cscf;

    c   = r->connection;
    rev = c->read;

    n = r->header_in->last - r->header_in->pos;

    if (n > 0)
    {
        return n;
    }

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    if (c->async_enable)
        n = c->recv(c, r->header_in->last,
                    r->header_in->end - r->header_in->last);
    else
    {
#endif
        if (rev->ready)
        {
            n = c->recv(c, r->header_in->last,
                        r->header_in->end - r->header_in->last);
        }
        else
        {
            n = NGX_AGAIN;
        }
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    }
#endif

    if (n == NGX_AGAIN)
    {
        if (!rev->timer_set)
        {
            cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
            ngx_add_timer(rev, cscf->client_header_timeout);
        }

        if (ngx_handle_read_event(rev, 0) != NGX_OK)
        {
            ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
            return NGX_ERROR;
        }

        return NGX_AGAIN;
    }

    if (n == 0)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, 0,
                      "client prematurely closed connection");
    }

    if (n == 0 || n == NGX_ERROR)
    {
        c->error       = 1;
        c->log->action = "reading client request headers";

        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
        return NGX_ERROR;
    }

    r->header_in->last += n;
#if (T_NGX_REQ_STATUS)
    c->received += n;
#endif

    return n;
}


static ngx_int_t
ngx_http_alloc_large_header_buffer(ngx_http_request_t *r,
                                   ngx_uint_t          request_line)
{
    u_char                   *old, *new;
    ngx_buf_t                *b;
    ngx_chain_t              *cl;
    ngx_http_connection_t    *hc;
    ngx_http_core_srv_conf_t *cscf;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http alloc large header buffer");

    if (request_line && r->state == 0)
    {
        /* the client fills up the buffer with "\r\n" */

        r->header_in->pos  = r->header_in->start;
        r->header_in->last = r->header_in->start;

        return NGX_OK;
    }

    old = request_line ? r->request_start : r->header_name_start;

    cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

    if (r->state != 0
        && (size_t)(r->header_in->pos - old)
               >= cscf->large_client_header_buffers.size)
    {
        return NGX_DECLINED;
    }

    hc = r->http_connection;

    if (hc->free)
    {
        cl       = hc->free;
        hc->free = cl->next;

        b = cl->buf;

        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                       "http large header free: %p %uz", b->pos,
                       b->end - b->last);
    }
    else if (hc->nbusy < cscf->large_client_header_buffers.num)
    {
        b = ngx_create_temp_buf(r->connection->pool,
                                cscf->large_client_header_buffers.size);
        if (b == NULL)
        {
            return NGX_ERROR;
        }

        cl = ngx_alloc_chain_link(r->connection->pool);
        if (cl == NULL)
        {
            return NGX_ERROR;
        }

        cl->buf = b;

        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                       "http large header alloc: %p %uz", b->pos,
                       b->end - b->last);
    }
    else
    {
        return NGX_DECLINED;
    }

    cl->next = hc->busy;
    hc->busy = cl;
    hc->nbusy++;

    if (r->state == 0)
    {
        /*
         * r->state == 0 means that a header line was parsed successfully
         * and we do not need to copy incomplete header line and
         * to relocate the parser header pointers
         */

        r->header_in = b;

        return NGX_OK;
    }

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http large header copy: %uz", r->header_in->pos - old);

    new = b->start;

    ngx_memcpy(new, old, r->header_in->pos - old);

    b->pos  = new + (r->header_in->pos - old);
    b->last = new + (r->header_in->pos - old);

    if (request_line)
    {
        r->request_start = new;

        if (r->request_end)
        {
            r->request_end = new + (r->request_end - old);
        }

        r->method_end = new + (r->method_end - old);

        r->uri_start = new + (r->uri_start - old);
        r->uri_end   = new + (r->uri_end - old);

        if (r->schema_start)
        {
            r->schema_start = new + (r->schema_start - old);
            r->schema_end   = new + (r->schema_end - old);
        }

#if (NGX_HTTP_PROXY_CONNECT)
        if (r->connect_host_start)
        {
            r->connect_host_start = new + (r->connect_host_start - old);
            if (r->connect_host_end)
            {
                r->connect_host_end = new + (r->connect_host_end - old);
            }

            if (r->connect_port_end)
            {
                r->connect_port_end = new + (r->connect_port_end - old);
            }
        }
#endif

        if (r->host_start)
        {
            r->host_start = new + (r->host_start - old);
            if (r->host_end)
            {
                r->host_end = new + (r->host_end - old);
            }
        }

        if (r->port_start)
        {
            r->port_start = new + (r->port_start - old);
            r->port_end   = new + (r->port_end - old);
        }

        if (r->uri_ext)
        {
            r->uri_ext = new + (r->uri_ext - old);
        }

        if (r->args_start)
        {
            r->args_start = new + (r->args_start - old);
        }

        if (r->http_protocol.data)
        {
            r->http_protocol.data = new + (r->http_protocol.data - old);
        }
    }
    else
    {
        r->header_name_start = new;
        r->header_name_end   = new + (r->header_name_end - old);
        r->header_start      = new + (r->header_start - old);
        r->header_end        = new + (r->header_end - old);
    }

    r->header_in = b;

    return NGX_OK;
}


static ngx_int_t
ngx_http_process_header_line(ngx_http_request_t *r, ngx_table_elt_t *h,
                             ngx_uint_t offset)
{
    ngx_table_elt_t **ph;

    ph = (ngx_table_elt_t **)((char *)&r->headers_in + offset);

    if (*ph == NULL)
    {
        *ph = h;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_process_unique_header_line(ngx_http_request_t *r, ngx_table_elt_t *h,
                                    ngx_uint_t offset)
{
    ngx_table_elt_t **ph;

    ph = (ngx_table_elt_t **)((char *)&r->headers_in + offset);

    if (*ph == NULL)
    {
        *ph = h;
        return NGX_OK;
    }

    ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                  "client sent duplicate header line: \"%V: %V\", "
                  "previous value: \"%V: %V\"",
                  &h->key, &h->value, &(*ph)->key, &(*ph)->value);

    ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);

    return NGX_ERROR;
}


static ngx_int_t
ngx_http_process_host(ngx_http_request_t *r, ngx_table_elt_t *h,
                      ngx_uint_t offset)
{
    ngx_int_t rc;
    ngx_str_t host;

    if (r->headers_in.host)
    {
        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                      "client sent duplicate host header: \"%V: %V\", "
                      "previous value: \"%V: %V\"",
                      &h->key, &h->value, &r->headers_in.host->key,
                      &r->headers_in.host->value);
        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
        return NGX_ERROR;
    }

    r->headers_in.host = h;

    host = h->value;

    rc = ngx_http_validate_host(&host, r->pool, 0);

    if (rc == NGX_DECLINED)
    {
        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                      "client sent invalid host header");
        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
        return NGX_ERROR;
    }

    if (rc == NGX_ERROR)
    {
        ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
        return NGX_ERROR;
    }

    if (r->headers_in.server.len)
    {
        return NGX_OK;
    }

    if (ngx_http_set_virtual_server(r, &host) == NGX_ERROR)
    {
        return NGX_ERROR;
    }

    r->headers_in.server = host;

    return NGX_OK;
}


static ngx_int_t
ngx_http_process_connection(ngx_http_request_t *r, ngx_table_elt_t *h,
                            ngx_uint_t offset)
{
    if (ngx_strcasestrn(h->value.data, "close", 5 - 1))
    {
        r->headers_in.connection_type = NGX_HTTP_CONNECTION_CLOSE;
    }
    else if (ngx_strcasestrn(h->value.data, "keep-alive", 10 - 1))
    {
        r->headers_in.connection_type = NGX_HTTP_CONNECTION_KEEP_ALIVE;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_process_user_agent(ngx_http_request_t *r, ngx_table_elt_t *h,
                            ngx_uint_t offset)
{
    u_char *user_agent, *msie;

    if (r->headers_in.user_agent)
    {
        return NGX_OK;
    }

    r->headers_in.user_agent = h;

    /* check some widespread browsers while the header is in CPU cache */

    user_agent = h->value.data;

    msie = ngx_strstrn(user_agent, "MSIE ", 5 - 1);

    if (msie && msie + 7 < user_agent + h->value.len)
    {
        r->headers_in.msie = 1;

        if (msie[6] == '.')
        {
            switch (msie[5])
            {
            case '4':
            case '5': r->headers_in.msie6 = 1; break;
            case '6':
                if (ngx_strstrn(msie + 8, "SV1", 3 - 1) == NULL)
                {
                    r->headers_in.msie6 = 1;
                }
                break;
            }
        }

#if 0
        /* MSIE ignores the SSL "close notify" alert */
        if (c->ssl) {
            c->ssl->no_send_shutdown = 1;
        }
#endif
    }

    if (ngx_strstrn(user_agent, "Opera", 5 - 1))
    {
        r->headers_in.opera = 1;
        r->headers_in.msie  = 0;
        r->headers_in.msie6 = 0;
    }

    if (!r->headers_in.msie && !r->headers_in.opera)
    {
        if (ngx_strstrn(user_agent, "Gecko/", 6 - 1))
        {
            r->headers_in.gecko = 1;
        }
        else if (ngx_strstrn(user_agent, "Chrome/", 7 - 1))
        {
            r->headers_in.chrome = 1;
        }
        else if (ngx_strstrn(user_agent, "Safari/", 7 - 1)
                 && ngx_strstrn(user_agent, "Mac OS X", 8 - 1))
        {
            r->headers_in.safari = 1;
        }
        else if (ngx_strstrn(user_agent, "Konqueror", 9 - 1))
        {
            r->headers_in.konqueror = 1;
        }
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_process_multi_header_lines(ngx_http_request_t *r, ngx_table_elt_t *h,
                                    ngx_uint_t offset)
{
    ngx_array_t      *headers;
    ngx_table_elt_t **ph;

    headers = (ngx_array_t *)((char *)&r->headers_in + offset);

    if (headers->elts == NULL)
    {
        if (ngx_array_init(headers, r->pool, 1, sizeof(ngx_table_elt_t *))
            != NGX_OK)
        {
            ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
            return NGX_ERROR;
        }
    }

    ph = ngx_array_push(headers);
    if (ph == NULL)
    {
        ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
        return NGX_ERROR;
    }

    *ph = h;
    return NGX_OK;
}


ngx_int_t
ngx_http_process_request_header(ngx_http_request_t *r)
{
    if (r->headers_in.server.len == 0
        && ngx_http_set_virtual_server(r, &r->headers_in.server) == NGX_ERROR)
    {
        return NGX_ERROR;
    }

    if (r->headers_in.host == NULL && r->http_version > NGX_HTTP_VERSION_10)
    {
        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                      "client sent HTTP/1.1 request without \"Host\" header");
        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
        return NGX_ERROR;
    }

    if (r->headers_in.content_length)
    {
        r->headers_in.content_length_n =
            ngx_atoof(r->headers_in.content_length->value.data,
                      r->headers_in.content_length->value.len);

        if (r->headers_in.content_length_n == NGX_ERROR)
        {
            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                          "client sent invalid \"Content-Length\" header");
            ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
            return NGX_ERROR;
        }
    }

    if (r->method == NGX_HTTP_TRACE)
    {
        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                      "client sent TRACE method");
        ngx_http_finalize_request(r, NGX_HTTP_NOT_ALLOWED);
        return NGX_ERROR;
    }

    if (r->headers_in.transfer_encoding)
    {
        if (r->headers_in.transfer_encoding->value.len == 7
            && ngx_strncasecmp(r->headers_in.transfer_encoding->value.data,
                               (u_char *)"chunked", 7)
                   == 0)
        {
            r->headers_in.content_length   = NULL;
            r->headers_in.content_length_n = -1;
            r->headers_in.chunked          = 1;
        }
        else
        {
            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                          "client sent unknown \"Transfer-Encoding\": \"%V\"",
                          &r->headers_in.transfer_encoding->value);
            ngx_http_finalize_request(r, NGX_HTTP_NOT_IMPLEMENTED);
            return NGX_ERROR;
        }
    }

    if (r->headers_in.connection_type == NGX_HTTP_CONNECTION_KEEP_ALIVE)
    {
        if (r->headers_in.keep_alive)
        {
            r->headers_in.keep_alive_n =
                ngx_atotm(r->headers_in.keep_alive->value.data,
                          r->headers_in.keep_alive->value.len);
        }
    }

    return NGX_OK;
}


void
ngx_http_process_request(ngx_http_request_t *r)
{
    ngx_connection_t *c;

    c = r->connection;

#if (NGX_HTTP_SSL && !T_NGX_HTTP_SSL_VCE)

    if (r->http_connection->ssl)
    {
        long                     rc;
        X509                    *cert;
        ngx_http_ssl_srv_conf_t *sscf;

        if (c->ssl == NULL)
        {
            ngx_log_error(NGX_LOG_INFO, c->log, 0,
                          "client sent plain HTTP request to HTTPS port");
            ngx_http_finalize_request(r, NGX_HTTP_TO_HTTPS);
            return;
        }

        sscf = ngx_http_get_module_srv_conf(r, ngx_http_ssl_module);

        if (sscf->verify)
        {
            rc = SSL_get_verify_result(c->ssl->connection);

            if (rc != X509_V_OK
                && (sscf->verify != 3 || !ngx_ssl_verify_error_optional(rc)))
            {
                ngx_log_error(NGX_LOG_INFO, c->log, 0,
                              "client SSL certificate verify error: (%l:%s)",
                              rc, X509_verify_cert_error_string(rc));

                ngx_ssl_remove_cached_session(
                    c->ssl->session_ctx,
                    (SSL_get0_session(c->ssl->connection)));

                ngx_http_finalize_request(r, NGX_HTTPS_CERT_ERROR);
                return;
            }

            if (sscf->verify == 1)
            {
                cert = SSL_get_peer_certificate(c->ssl->connection);

                if (cert == NULL)
                {
                    ngx_log_error(NGX_LOG_INFO, c->log, 0,
                                  "client sent no required SSL certificate");

                    ngx_ssl_remove_cached_session(
                        c->ssl->session_ctx,
                        (SSL_get0_session(c->ssl->connection)));

                    ngx_http_finalize_request(r, NGX_HTTPS_NO_CERT);
                    return;
                }

                X509_free(cert);
            }
        }
    }

#endif

    if (c->read->timer_set)
    {
        ngx_del_timer(c->read);
    }

#if (NGX_STAT_STUB)
    (void)ngx_atomic_fetch_add(ngx_stat_reading, -1);
    r->stat_reading = 0;
    (void)ngx_atomic_fetch_add(ngx_stat_writing, 1);
    r->stat_writing = 1;
#endif

    c->read->handler      = ngx_http_request_handler;
    c->write->handler     = ngx_http_request_handler;
    r->read_event_handler = ngx_http_block_reading;

    ngx_http_handler(r);
}


static ngx_int_t
ngx_http_validate_host(ngx_str_t *host, ngx_pool_t *pool, ngx_uint_t alloc)
{
    u_char *h, ch;
    size_t  i, dot_pos, host_len;

    enum
    {
        sw_usual = 0,
        sw_literal,
        sw_rest
    } state;

    dot_pos  = host->len;
    host_len = host->len;

    h = host->data;

    state = sw_usual;

    for (i = 0; i < host->len; i++)
    {
        ch = h[i];

        switch (ch)
        {
        case '.':
            if (dot_pos == i - 1)
            {
                return NGX_DECLINED;
            }
            dot_pos = i;
            break;

        case ':':
            if (state == sw_usual)
            {
                host_len = i;
                state    = sw_rest;
            }
            break;

        case '[':
            if (i == 0)
            {
                state = sw_literal;
            }
            break;

        case ']':
            if (state == sw_literal)
            {
                host_len = i + 1;
                state    = sw_rest;
            }
            break;

        case '\0': return NGX_DECLINED;

        default:

            if (ngx_path_separator(ch))
            {
                return NGX_DECLINED;
            }

            if (ch >= 'A' && ch <= 'Z')
            {
                alloc = 1;
            }

            break;
        }
    }

    if (dot_pos == host_len - 1)
    {
        host_len--;
    }

    if (host_len == 0)
    {
        return NGX_DECLINED;
    }

    if (alloc)
    {
        host->data = ngx_pnalloc(pool, host_len);
        if (host->data == NULL)
        {
            return NGX_ERROR;
        }

        ngx_strlow(host->data, h, host_len);
    }

    host->len = host_len;

    return NGX_OK;
}


static ngx_int_t
ngx_http_set_virtual_server(ngx_http_request_t *r, ngx_str_t *host)
{
    ngx_int_t                 rc;
    ngx_http_connection_t    *hc;
    ngx_http_core_loc_conf_t *clcf;
    ngx_http_core_srv_conf_t *cscf;

#if (NGX_SUPPRESS_WARN)
    cscf = NULL;
#endif

    hc = r->http_connection;

#if (NGX_HTTP_SSL && defined SSL_CTRL_SET_TLSEXT_HOSTNAME)

    if (hc->ssl_servername)
    {
        if (hc->ssl_servername->len == host->len
            && ngx_strncmp(hc->ssl_servername->data, host->data, host->len)
                   == 0)
        {
#if (NGX_PCRE)
            if (hc->ssl_servername_regex
                && ngx_http_regex_exec(r, hc->ssl_servername_regex,
                                       hc->ssl_servername)
                       != NGX_OK)
            {
                ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
                return NGX_ERROR;
            }
#endif
            return NGX_OK;
        }
    }

#endif

    rc = ngx_http_find_virtual_server(
        r->connection, hc->addr_conf->virtual_names, host, r, &cscf);

    if (rc == NGX_ERROR)
    {
        ngx_http_close_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
        return NGX_ERROR;
    }

#if (NGX_HTTP_SSL && defined SSL_CTRL_SET_TLSEXT_HOSTNAME)

    if (hc->ssl_servername)
    {
        ngx_http_ssl_srv_conf_t *sscf;

        if (rc == NGX_DECLINED)
        {
            cscf = hc->addr_conf->default_server;
            rc   = NGX_OK;
        }

        sscf = ngx_http_get_module_srv_conf(cscf->ctx, ngx_http_ssl_module);

        if (sscf->verify)
        {
            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                          "client attempted to request the server name "
                          "different from the one that was negotiated");
            ngx_http_finalize_request(r, NGX_HTTP_MISDIRECTED_REQUEST);
            return NGX_ERROR;
        }
    }

#endif

    if (rc == NGX_DECLINED)
    {
        return NGX_OK;
    }

    r->srv_conf = cscf->ctx->srv_conf;
    r->loc_conf = cscf->ctx->loc_conf;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    ngx_set_connection_log(r->connection, clcf->error_log);

    return NGX_OK;
}


static ngx_int_t
ngx_http_find_virtual_server(ngx_connection_t         *c,
                             ngx_http_virtual_names_t *virtual_names,
                             ngx_str_t *host, ngx_http_request_t *r,
                             ngx_http_core_srv_conf_t **cscfp)
{
    ngx_http_core_srv_conf_t *cscf;

    if (virtual_names == NULL)
    {
        return NGX_DECLINED;
    }

    cscf = ngx_hash_find_combined(&virtual_names->names,
                                  ngx_hash_key(host->data, host->len),
                                  host->data, host->len);

    if (cscf)
    {
        *cscfp = cscf;
        return NGX_OK;
    }

#if (NGX_PCRE)

    if (host->len && virtual_names->nregex)
    {
        ngx_int_t               n;
        ngx_uint_t              i;
        ngx_http_server_name_t *sn;

        sn = virtual_names->regex;

#if (NGX_HTTP_SSL && defined SSL_CTRL_SET_TLSEXT_HOSTNAME)

        if (r == NULL)
        {
            ngx_http_connection_t *hc;

            for (i = 0; i < virtual_names->nregex; i++)
            {
                n = ngx_regex_exec(sn[i].regex->regex, host, NULL, 0);

                if (n == NGX_REGEX_NO_MATCHED)
                {
                    continue;
                }

                if (n >= 0)
                {
                    hc                       = c->data;
                    hc->ssl_servername_regex = sn[i].regex;

                    *cscfp = sn[i].server;
                    return NGX_OK;
                }

                ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                              ngx_regex_exec_n " failed: %i "
                                               "on \"%V\" using \"%V\"",
                              n, host, &sn[i].regex->name);

                return NGX_ERROR;
            }

            return NGX_DECLINED;
        }

#endif /* NGX_HTTP_SSL && defined SSL_CTRL_SET_TLSEXT_HOSTNAME */

        for (i = 0; i < virtual_names->nregex; i++)
        {
            n = ngx_http_regex_exec(r, sn[i].regex, host);

            if (n == NGX_DECLINED)
            {
                continue;
            }

            if (n == NGX_OK)
            {
                *cscfp = sn[i].server;
                return NGX_OK;
            }

            return NGX_ERROR;
        }
    }

#endif /* NGX_PCRE */

    return NGX_DECLINED;
}


static void
ngx_http_request_handler(ngx_event_t *ev)
{
    ngx_connection_t   *c;
    ngx_http_request_t *r;

    c = ev->data;
    r = c->data;

    ngx_http_set_log_request(c->log, r);

    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http run request: \"%V?%V\"",
                   &r->uri, &r->args);

    if (c->close)
    {
        r->main->count++;
        ngx_http_terminate_request(r, 0);
        ngx_http_run_posted_requests(c);
        return;
    }

    if (ev->delayed && ev->timedout)
    {
        ev->delayed  = 0;
        ev->timedout = 0;
    }

    if (ev->write)
    {
        r->write_event_handler(r);
    }
    else
    {
        r->read_event_handler(r);
    }

    ngx_http_run_posted_requests(c);
}


void
ngx_http_run_posted_requests(ngx_connection_t *c)
{
    ngx_http_request_t        *r;
    ngx_http_posted_request_t *pr;

    for (;;)
    {
        if (c->destroyed)
        {
            return;
        }

        r  = c->data;
        pr = r->main->posted_requests;

        if (pr == NULL)
        {
            return;
        }

        r->main->posted_requests = pr->next;

        r = pr->request;

        ngx_http_set_log_request(c->log, r);

        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                       "http posted request: \"%V?%V\"", &r->uri, &r->args);

        r->write_event_handler(r);
    }
}


ngx_int_t
ngx_http_post_request(ngx_http_request_t *r, ngx_http_posted_request_t *pr)
{
    ngx_http_posted_request_t **p;

    if (pr == NULL)
    {
        pr = ngx_palloc(r->pool, sizeof(ngx_http_posted_request_t));
        if (pr == NULL)
        {
            return NGX_ERROR;
        }
    }

    pr->request = r;
    pr->next    = NULL;

    for (p = &r->main->posted_requests; *p; p = &(*p)->next)
    { /* void */
    }

    *p = pr;

    return NGX_OK;
}


void
ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
{
    ngx_connection_t         *c;
    ngx_http_request_t       *pr;
    ngx_http_core_loc_conf_t *clcf;

    c = r->connection;

    ngx_log_debug5(NGX_LOG_DEBUG_HTTP, c->log, 0,
                   "http finalize request: %i, \"%V?%V\" a:%d, c:%d", rc,
                   &r->uri, &r->args, r == c->data, r->main->count);

    if (rc == NGX_DONE)
    {
        ngx_http_finalize_connection(r);
        return;
    }

    if (rc == NGX_OK && r->filter_finalize)
    {
        c->error = 1;
    }

    if (rc == NGX_DECLINED)
    {
        r->content_handler     = NULL;
        r->write_event_handler = ngx_http_core_run_phases;
        ngx_http_core_run_phases(r);
        return;
    }

    if (r != r->main && r->post_subrequest)
    {
        rc = r->post_subrequest->handler(r, r->post_subrequest->data, rc);
    }

    if (rc == NGX_ERROR || rc == NGX_HTTP_REQUEST_TIME_OUT
        || rc == NGX_HTTP_CLIENT_CLOSED_REQUEST || c->error)
    {
        if (ngx_http_post_action(r) == NGX_OK)
        {
            return;
        }

        ngx_http_terminate_request(r, rc);
        return;
    }

    if (rc >= NGX_HTTP_SPECIAL_RESPONSE || rc == NGX_HTTP_CREATED
        || rc == NGX_HTTP_NO_CONTENT)
    {
        if (rc == NGX_HTTP_CLOSE)
        {
            c->timedout = 1;
            ngx_http_terminate_request(r, rc);
            return;
        }

        if (r == r->main)
        {
            if (c->read->timer_set)
            {
                ngx_del_timer(c->read);
            }

            if (c->write->timer_set)
            {
                ngx_del_timer(c->write);
            }
        }

        c->read->handler  = ngx_http_request_handler;
        c->write->handler = ngx_http_request_handler;

        ngx_http_finalize_request(r, ngx_http_special_response_handler(r, rc));
        return;
    }

    if (r != r->main)
    {
        if (r->buffered || r->postponed)
        {
            if (ngx_http_set_write_handler(r) != NGX_OK)
            {
                ngx_http_terminate_request(r, 0);
            }

            return;
        }

        pr = r->parent;

        if (r == c->data || r->background)
        {
            if (!r->logged)
            {
                clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

                if (clcf->log_subrequest)
                {
                    ngx_http_log_request(r);
                }

                r->logged = 1;
            }
            else
            {
                ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                              "subrequest: \"%V?%V\" logged again", &r->uri,
                              &r->args);
            }

            r->done = 1;

            if (r->background)
            {
                ngx_http_finalize_connection(r);
                return;
            }

            r->main->count--;

            if (pr->postponed && pr->postponed->request == r)
            {
                pr->postponed = pr->postponed->next;
            }

            c->data = pr;
        }
        else
        {
            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                           "http finalize non-active request: \"%V?%V\"",
                           &r->uri, &r->args);

            r->write_event_handler = ngx_http_request_finalizer;

            if (r->waited)
            {
                r->done = 1;
            }
        }

        if (ngx_http_post_request(pr, NULL) != NGX_OK)
        {
            r->main->count++;
            ngx_http_terminate_request(r, 0);
            return;
        }

        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                       "http wake parent request: \"%V?%V\"", &pr->uri,
                       &pr->args);

        return;
    }

    if (r->buffered || c->buffered || r->postponed)
    {
        if (ngx_http_set_write_handler(r) != NGX_OK)
        {
            ngx_http_terminate_request(r, 0);
        }

        return;
    }

    if (r != c->data)
    {
        ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                      "http finalize non-active request: \"%V?%V\"", &r->uri,
                      &r->args);
        return;
    }

    r->done = 1;

    r->read_event_handler  = ngx_http_block_reading;
    r->write_event_handler = ngx_http_request_empty_handler;

    if (!r->post_action)
    {
        r->request_complete = 1;
    }

    if (ngx_http_post_action(r) == NGX_OK)
    {
        return;
    }

    if (c->read->timer_set)
    {
        ngx_del_timer(c->read);
    }

    if (c->write->timer_set)
    {
        c->write->delayed = 0;
        ngx_del_timer(c->write);
    }

    if (c->read->eof)
    {
        ngx_http_close_request(r, 0);
        return;
    }

    ngx_http_finalize_connection(r);
}


static void
ngx_http_terminate_request(ngx_http_request_t *r, ngx_int_t rc)
{
    ngx_http_cleanup_t   *cln;
    ngx_http_request_t   *mr;
    ngx_http_ephemeral_t *e;

    mr = r->main;

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http terminate request count:%d", mr->count);

    if (rc > 0 && (mr->headers_out.status == 0 || mr->connection->sent == 0))
    {
        mr->headers_out.status = rc;
    }

    cln         = mr->cleanup;
    mr->cleanup = NULL;

    while (cln)
    {
        if (cln->handler)
        {
            cln->handler(cln->data);
        }

        cln = cln->next;
    }

    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http terminate cleanup count:%d blk:%d", mr->count,
                   mr->blocked);

    if (mr->write_event_handler)
    {
        if (mr->blocked)
        {
            r->connection->error   = 1;
            r->write_event_handler = ngx_http_request_finalizer;
            return;
        }

        e                       = ngx_http_ephemeral(mr);
        mr->posted_requests     = NULL;
        mr->write_event_handler = ngx_http_terminate_handler;
        (void)ngx_http_post_request(mr, &e->terminal_posted_request);
        return;
    }

    ngx_http_close_request(mr, rc);
}


static void
ngx_http_terminate_handler(ngx_http_request_t *r)
{
    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http terminate handler count:%d", r->count);

    r->count = 1;

    ngx_http_close_request(r, 0);
}


static void
ngx_http_finalize_connection(ngx_http_request_t *r)
{
    ngx_http_core_loc_conf_t *clcf;

#if (NGX_HTTP_V2)
    if (r->stream)
    {
        ngx_http_close_request(r, 0);
        return;
    }
#endif

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    if (r->main->count != 1)
    {
        if (r->discard_body)
        {
            r->read_event_handler = ngx_http_discarded_request_body_handler;
            ngx_add_timer(r->connection->read, clcf->lingering_timeout);

            if (r->lingering_time == 0)
            {
                r->lingering_time =
                    ngx_time() + (time_t)(clcf->lingering_time / 1000);
            }
        }

        ngx_http_close_request(r, 0);
        return;
    }

    r = r->main;

    if (r->reading_body)
    {
        r->keepalive       = 0;
        r->lingering_close = 1;
    }

    if (!ngx_terminate && !ngx_exiting && r->keepalive
        && clcf->keepalive_timeout > 0)
    {
        ngx_http_set_keepalive(r);
        return;
    }

    if (clcf->lingering_close == NGX_HTTP_LINGERING_ALWAYS
        || (clcf->lingering_close == NGX_HTTP_LINGERING_ON
            && (r->lingering_close || r->header_in->pos < r->header_in->last
                || r->connection->read->ready)))
    {
        ngx_http_set_lingering_close(r);
        return;
    }

    ngx_http_close_request(r, 0);
}


static ngx_int_t
ngx_http_set_write_handler(ngx_http_request_t *r)
{
    ngx_event_t              *wev;
    ngx_http_core_loc_conf_t *clcf;

    r->http_state = NGX_HTTP_WRITING_REQUEST_STATE;

    r->read_event_handler  = r->discard_body
                                 ? ngx_http_discarded_request_body_handler
                                 : ngx_http_test_reading;
    r->write_event_handler = ngx_http_writer;

    wev = r->connection->write;

    if (wev->ready && wev->delayed)
    {
        return NGX_OK;
    }

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
    if (!wev->delayed)
    {
        ngx_add_timer(wev, clcf->send_timeout);
    }

    if (ngx_handle_write_event(wev, clcf->send_lowat) != NGX_OK)
    {
        ngx_http_close_request(r, 0);
        return NGX_ERROR;
    }

    return NGX_OK;
}


static void
ngx_http_writer(ngx_http_request_t *r)
{
    ngx_int_t                 rc;
    ngx_event_t              *wev;
    ngx_connection_t         *c;
    ngx_http_core_loc_conf_t *clcf;

    c   = r->connection;
    wev = c->write;

    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, wev->log, 0,
                   "http writer handler: \"%V?%V\"", &r->uri, &r->args);

    clcf = ngx_http_get_module_loc_conf(r->main, ngx_http_core_module);

    if (wev->timedout)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
        c->timedout = 1;

        ngx_http_finalize_request(r, NGX_HTTP_REQUEST_TIME_OUT);
        return;
    }

    if (wev->delayed || r->aio)
    {
        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, wev->log, 0, "http writer delayed");

        if (!wev->delayed)
        {
            ngx_add_timer(wev, clcf->send_timeout);
        }

        if (ngx_handle_write_event(wev, clcf->send_lowat) != NGX_OK)
        {
            ngx_http_close_request(r, 0);
        }

        return;
    }

    rc = ngx_http_output_filter(r, NULL);

    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
                   "http writer output filter: %i, \"%V?%V\"", rc, &r->uri,
                   &r->args);

    if (rc == NGX_ERROR)
    {
        ngx_http_finalize_request(r, rc);
        return;
    }

    if (r->buffered || r->postponed || (r == r->main && c->buffered))
    {
        if (!wev->delayed)
        {
            ngx_add_timer(wev, clcf->send_timeout);
        }

        if (ngx_handle_write_event(wev, clcf->send_lowat) != NGX_OK)
        {
            ngx_http_close_request(r, 0);
        }

        return;
    }

    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, wev->log, 0,
                   "http writer done: \"%V?%V\"", &r->uri, &r->args);

    r->write_event_handler = ngx_http_request_empty_handler;

    ngx_http_finalize_request(r, rc);
}


static void
ngx_http_request_finalizer(ngx_http_request_t *r)
{
    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http finalizer done: \"%V?%V\"", &r->uri, &r->args);

    ngx_http_finalize_request(r, 0);
}


void
ngx_http_block_reading(ngx_http_request_t *r)
{
    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http reading blocked");

    /* aio does not call this handler */

    if ((ngx_event_flags & NGX_USE_LEVEL_EVENT) && r->connection->read->active)
    {
        if (ngx_del_event(r->connection->read, NGX_READ_EVENT, 0) != NGX_OK)
        {
            ngx_http_close_request(r, 0);
        }
    }
}


void
ngx_http_test_reading(ngx_http_request_t *r)
{
    int               n;
    char              buf[1];
    ngx_err_t         err;
    ngx_event_t      *rev;
    ngx_connection_t *c;

    c   = r->connection;
    rev = c->read;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http test reading");

#if (NGX_HTTP_V2)

    if (r->stream)
    {
        if (c->error)
        {
            err = 0;
            goto closed;
        }

        return;
    }

#endif

#if (NGX_HAVE_KQUEUE)

    if (ngx_event_flags & NGX_USE_KQUEUE_EVENT)
    {
        if (!rev->pending_eof)
        {
            return;
        }

        rev->eof = 1;
        c->error = 1;
        err      = rev->kq_errno;

        goto closed;
    }

#endif

#if (NGX_HAVE_EPOLLRDHUP)

    if ((ngx_event_flags & NGX_USE_EPOLL_EVENT) && ngx_use_epoll_rdhup)
    {
        socklen_t len;

        if (!rev->pending_eof)
        {
            return;
        }

        rev->eof = 1;
        c->error = 1;

        err = 0;
        len = sizeof(ngx_err_t);

        /*
         * BSDs and Linux return 0 and set a pending error in err
         * Solaris returns -1 and sets errno
         */

        if (getsockopt(c->fd, SOL_SOCKET, SO_ERROR, (void *)&err, &len) == -1)
        {
            err = ngx_socket_errno;
        }

        goto closed;
    }

#endif

    n = recv(c->fd, buf, 1, MSG_PEEK);

    if (n == 0)
    {
        rev->eof = 1;
        c->error = 1;
        err      = 0;

        goto closed;
    }
    else if (n == -1)
    {
        err = ngx_socket_errno;

        if (err != NGX_EAGAIN)
        {
            rev->eof = 1;
            c->error = 1;

            goto closed;
        }
    }

    /* aio does not call this handler */

    if ((ngx_event_flags & NGX_USE_LEVEL_EVENT) && rev->active)
    {
        if (ngx_del_event(rev, NGX_READ_EVENT, 0) != NGX_OK)
        {
            ngx_http_close_request(r, 0);
        }
    }

    return;

closed:

    if (err)
    {
        rev->error = 1;
    }

    ngx_log_error(NGX_LOG_INFO, c->log, err,
                  "client prematurely closed connection");

    ngx_http_finalize_request(r, NGX_HTTP_CLIENT_CLOSED_REQUEST);
}


static void
ngx_http_set_keepalive(ngx_http_request_t *r)
{
    int                       tcp_nodelay;
    ngx_buf_t                *b, *f;
    ngx_chain_t              *cl, *ln;
    ngx_event_t              *rev, *wev;
    ngx_connection_t         *c;
    ngx_http_connection_t    *hc;
    ngx_http_core_loc_conf_t *clcf;

    c   = r->connection;
    rev = c->read;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "set http keepalive handler");

    if (r->discard_body)
    {
        r->write_event_handler = ngx_http_request_empty_handler;
        r->lingering_time = ngx_time() + (time_t)(clcf->lingering_time / 1000);
        ngx_add_timer(rev, clcf->lingering_timeout);
        return;
    }

    c->log->action = "closing request";

    hc = r->http_connection;
    b  = r->header_in;

    if (b->pos < b->last)
    {
        /* the pipelined request */

        if (b != c->buffer)
        {
            /*
             * If the large header buffers were allocated while the previous
             * request processing then we do not use c->buffer for
             * the pipelined request (see ngx_http_create_request()).
             *
             * Now we would move the large header buffers to the free list.
             */

            for (cl = hc->busy; cl; /* void */)
            {
                ln = cl;
                cl = cl->next;

                if (ln->buf == b)
                {
                    ngx_free_chain(c->pool, ln);
                    continue;
                }

                f       = ln->buf;
                f->pos  = f->start;
                f->last = f->start;

                ln->next = hc->free;
                hc->free = ln;
            }

            cl = ngx_alloc_chain_link(c->pool);
            if (cl == NULL)
            {
                ngx_http_close_request(r, 0);
                return;
            }

            cl->buf  = b;
            cl->next = NULL;

            hc->busy  = cl;
            hc->nbusy = 1;
        }
    }

    /* guard against recursive call from ngx_http_finalize_connection() */
    r->keepalive = 0;

    ngx_http_free_request(r, 0);

    c->data = hc;

    if (ngx_handle_read_event(rev, 0) != NGX_OK)
    {
        ngx_http_close_connection(c);
        return;
    }

    wev          = c->write;
    wev->handler = ngx_http_empty_handler;

    if (b->pos < b->last)
    {
        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "pipelined request");

        c->log->action = "reading client pipelined request line";

        r = ngx_http_create_request(c);
        if (r == NULL)
        {
            ngx_http_close_connection(c);
            return;
        }

        r->pipeline = 1;

        c->data = r;

        c->sent      = 0;
        c->destroyed = 0;

#if (T_NGX_REQ_STATUS)
        /* bytes in the buffer have already been counted */
        c->received = 0;
#endif

        if (rev->timer_set)
        {
            ngx_del_timer(rev);
        }

        rev->handler = ngx_http_process_request_line;
        ngx_post_event(rev, &ngx_posted_events);
        return;
    }

    /*
     * To keep a memory footprint as small as possible for an idle keepalive
     * connection we try to free c->buffer's memory if it was allocated outside
     * the c->pool.  The large header buffers are always allocated outside the
     * c->pool and are freed too.
     */

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    /* For the Async implementation we need the same buffer to be used
     * again on any async calls that have not completed.
     * As such we need to turn off this optimisation if an async request
     * is still in progress.
     */
    if ((c->async_enable && !ngx_ssl_waiting_for_async(c)) || !c->async_enable)
    {
#endif
        b = c->buffer;

        if (ngx_pfree(c->pool, b->start) == NGX_OK)
        {
            /*
             * the special note for ngx_http_keepalive_handler() that
             * c->buffer's memory was freed
             */

            b->pos = NULL;
        }
        else
        {
            b->pos  = b->start;
            b->last = b->start;
        }

        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "hc free: %p", hc->free);

        if (hc->free)
        {
            for (cl = hc->free; cl; /* void */)
            {
                ln = cl;
                cl = cl->next;
                ngx_pfree(c->pool, ln->buf->start);
                ngx_free_chain(c->pool, ln);
            }

            hc->free = NULL;
        }

        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "hc busy: %p %i",
                       hc->busy, hc->nbusy);

        if (hc->busy)
        {
            for (cl = hc->busy; cl; /* void */)
            {
                ln = cl;
                cl = cl->next;
                ngx_pfree(c->pool, ln->buf->start);
                ngx_free_chain(c->pool, ln);
            }

            hc->busy  = NULL;
            hc->nbusy = 0;
        }
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    }
#endif

#if (NGX_HTTP_SSL)
    if (c->ssl)
    {
        ngx_ssl_free_buffer(c);
    }
#endif

    rev->handler = ngx_http_keepalive_handler;

    if (wev->active && (ngx_event_flags & NGX_USE_LEVEL_EVENT))
    {
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        if (c->async_enable && ngx_del_async_conn)
        {
            if (c->num_async_fds)
            {
                ngx_del_async_conn(c, NGX_DISABLE_EVENT);
                c->num_async_fds--;
            }
        }
#endif
        if (ngx_del_event(wev, NGX_WRITE_EVENT, 0) != NGX_OK)
        {
            ngx_http_close_connection(c);
            return;
        }
    }

    c->log->action = "keepalive";

    if (c->tcp_nopush == NGX_TCP_NOPUSH_SET)
    {
        if (ngx_tcp_push(c->fd) == -1)
        {
            ngx_connection_error(c, ngx_socket_errno, ngx_tcp_push_n " failed");
            ngx_http_close_connection(c);
            return;
        }

        c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
        tcp_nodelay   = ngx_tcp_nodelay_and_tcp_nopush ? 1 : 0;
    }
    else
    {
        tcp_nodelay = 1;
    }

    if (tcp_nodelay && clcf->tcp_nodelay && ngx_tcp_nodelay(c) != NGX_OK)
    {
        ngx_http_close_connection(c);
        return;
    }

#if 0
    /* if ngx_http_request_t was freed then we need some other place */
    r->http_state = NGX_HTTP_KEEPALIVE_STATE;
#endif

    c->idle = 1;
    ngx_reusable_connection(c, 1);

    ngx_add_timer(rev, clcf->keepalive_timeout);

    if (rev->ready)
    {
        ngx_post_event(rev, &ngx_posted_events);
    }
}


static void
ngx_http_keepalive_handler(ngx_event_t *rev)
{
    size_t            size;
    ssize_t           n;
    ngx_buf_t        *b;
    ngx_connection_t *c;

    c = rev->data;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http keepalive handler");

    if (rev->timedout || c->close)
    {
        ngx_http_close_connection(c);
        return;
    }

#if (NGX_HAVE_KQUEUE)

    if (ngx_event_flags & NGX_USE_KQUEUE_EVENT)
    {
        if (rev->pending_eof)
        {
            c->log->handler = NULL;
            ngx_log_error(NGX_LOG_INFO, c->log, rev->kq_errno,
                          "kevent() reported that client %V closed "
                          "keepalive connection",
                          &c->addr_text);
#if (NGX_HTTP_SSL)
            if (c->ssl)
            {
                c->ssl->no_send_shutdown = 1;
            }
#endif
            ngx_http_close_connection(c);
            return;
        }
    }

#endif

    b    = c->buffer;
    size = b->end - b->start;

    if (b->pos == NULL)
    {
        /*
         * The c->buffer's memory was freed by ngx_http_set_keepalive().
         * However, the c->buffer->start and c->buffer->end were not changed
         * to keep the buffer size.
         */

        b->pos = ngx_palloc(c->pool, size);
        if (b->pos == NULL)
        {
            ngx_http_close_connection(c);
            return;
        }

        b->start = b->pos;
        b->last  = b->pos;
        b->end   = b->pos + size;
    }

    /*
     * MSIE closes a keepalive connection with RST flag
     * so we ignore ECONNRESET here.
     */

    c->log_error = NGX_ERROR_IGNORE_ECONNRESET;
    ngx_set_socket_errno(0);

    n            = c->recv(c, b->last, size);
    c->log_error = NGX_ERROR_INFO;

    if (n == NGX_AGAIN)
    {
        if (ngx_handle_read_event(rev, 0) != NGX_OK)
        {
            ngx_http_close_connection(c);
            return;
        }

        /*
         * Like ngx_http_set_keepalive() we are trying to not hold
         * c->buffer's memory for a keepalive connection.
         */

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        /* For the Asynch implementation we need the same buffer to be used
         * on subsequent read requests. As such we need to turn off this
         * optimisation that frees the buffer between invocations as may end up
         * with a buffer that is at a different address */
        if ((c->async_enable && !ngx_ssl_waiting_for_async(c))
            || !c->async_enable)
        {
#endif
            if (ngx_pfree(c->pool, b->start) == NGX_OK)
            {
                /*
                 * the special note that c->buffer's memory was freed
                 */

                b->pos = NULL;
            }
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        }
#endif

        return;
    }

    if (n == NGX_ERROR)
    {
        ngx_http_close_connection(c);
        return;
    }

    c->log->handler = NULL;

    if (n == 0)
    {
        ngx_log_error(NGX_LOG_INFO, c->log, ngx_socket_errno,
                      "client %V closed keepalive connection", &c->addr_text);
        ngx_http_close_connection(c);
        return;
    }

    b->last += n;

    c->log->handler = ngx_http_log_error;
    c->log->action  = "reading client request line";

    c->idle = 0;
    ngx_reusable_connection(c, 0);

    c->data = ngx_http_create_request(c);
    if (c->data == NULL)
    {
        ngx_http_close_connection(c);
        return;
    }

    c->sent      = 0;
    c->destroyed = 0;
#if (T_NGX_REQ_STATUS)
    c->received = n;
#endif

    ngx_del_timer(rev);

    rev->handler = ngx_http_process_request_line;
    ngx_http_process_request_line(rev);
}


static void
ngx_http_set_lingering_close(ngx_http_request_t *r)
{
    ngx_event_t              *rev, *wev;
    ngx_connection_t         *c;
    ngx_http_core_loc_conf_t *clcf;

    c = r->connection;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    rev          = c->read;
    rev->handler = ngx_http_lingering_close_handler;

    r->lingering_time = ngx_time() + (time_t)(clcf->lingering_time / 1000);
    ngx_add_timer(rev, clcf->lingering_timeout);

    if (ngx_handle_read_event(rev, 0) != NGX_OK)
    {
        ngx_http_close_request(r, 0);
        return;
    }

    wev          = c->write;
    wev->handler = ngx_http_empty_handler;

    if (wev->active && (ngx_event_flags & NGX_USE_LEVEL_EVENT))
    {
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        if (c->async_enable && ngx_del_async_conn)
        {
            if (c->num_async_fds)
            {
                ngx_del_async_conn(c, NGX_DISABLE_EVENT);
                c->num_async_fds--;
            }
        }
#endif
        if (ngx_del_event(wev, NGX_WRITE_EVENT, 0) != NGX_OK)
        {
            ngx_http_close_request(r, 0);
            return;
        }
    }

    if (ngx_shutdown_socket(c->fd, NGX_WRITE_SHUTDOWN) == -1)
    {
        ngx_connection_error(c, ngx_socket_errno,
                             ngx_shutdown_socket_n " failed");
        ngx_http_close_request(r, 0);
        return;
    }

    if (rev->ready)
    {
        ngx_http_lingering_close_handler(rev);
    }
}


static void
ngx_http_lingering_close_handler(ngx_event_t *rev)
{
    ssize_t                   n;
    ngx_msec_t                timer;
    ngx_connection_t         *c;
    ngx_http_request_t       *r;
    ngx_http_core_loc_conf_t *clcf;
    u_char                    buffer[NGX_HTTP_LINGERING_BUFFER_SIZE];

    c = rev->data;
    r = c->data;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
                   "http lingering close handler");

    if (rev->timedout)
    {
        ngx_http_close_request(r, 0);
        return;
    }

    timer = (ngx_msec_t)r->lingering_time - (ngx_msec_t)ngx_time();
    if ((ngx_msec_int_t)timer <= 0)
    {
        ngx_http_close_request(r, 0);
        return;
    }

    do
    {
        n = c->recv(c, buffer, NGX_HTTP_LINGERING_BUFFER_SIZE);

        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "lingering read: %z", n);

        if (n == NGX_AGAIN)
        {
            break;
        }

        if (n == NGX_ERROR || n == 0)
        {
            ngx_http_close_request(r, 0);
            return;
        }

#if (T_NGX_REQ_STATUS)
        c->received += n;
#endif

    } while (rev->ready);

    if (ngx_handle_read_event(rev, 0) != NGX_OK)
    {
        ngx_http_close_request(r, 0);
        return;
    }

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    timer *= 1000;

    if (timer > clcf->lingering_timeout)
    {
        timer = clcf->lingering_timeout;
    }

    ngx_add_timer(rev, timer);
}


void
ngx_http_empty_handler(ngx_event_t *wev)
{
    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, wev->log, 0, "http empty handler");

    return;
}


void
ngx_http_request_empty_handler(ngx_http_request_t *r)
{
    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "http request empty handler");

    return;
}


ngx_int_t
ngx_http_send_special(ngx_http_request_t *r, ngx_uint_t flags)
{
    ngx_buf_t  *b;
    ngx_chain_t out;

    b = ngx_calloc_buf(r->pool);
    if (b == NULL)
    {
        return NGX_ERROR;
    }

    if (flags & NGX_HTTP_LAST)
    {
        if (r == r->main && !r->post_action)
        {
            b->last_buf = 1;
        }
        else
        {
            b->sync          = 1;
            b->last_in_chain = 1;
        }
    }

    if (flags & NGX_HTTP_FLUSH)
    {
        b->flush = 1;
    }

    out.buf  = b;
    out.next = NULL;

    return ngx_http_output_filter(r, &out);
}


static ngx_int_t
ngx_http_post_action(ngx_http_request_t *r)
{
    ngx_http_core_loc_conf_t *clcf;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    if (clcf->post_action.data == NULL)
    {
        return NGX_DECLINED;
    }

    if (r->post_action && r->uri_changes == 0)
    {
        return NGX_DECLINED;
    }

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "post action: \"%V\"", &clcf->post_action);

    r->main->count--;

    r->http_version = NGX_HTTP_VERSION_9;
    r->header_only  = 1;
    r->post_action  = 1;

    r->read_event_handler = ngx_http_block_reading;

    if (clcf->post_action.data[0] == '/')
    {
        ngx_http_internal_redirect(r, &clcf->post_action, NULL);
    }
    else
    {
        ngx_http_named_location(r, &clcf->post_action);
    }

    return NGX_OK;
}


static void
ngx_http_close_request(ngx_http_request_t *r, ngx_int_t rc)
{
    ngx_connection_t *c;

    r = r->main;
    c = r->connection;

    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                   "http request count:%d blk:%d", r->count, r->blocked);

    if (r->count == 0)
    {
        ngx_log_error(NGX_LOG_ALERT, c->log, 0, "http request count is zero");
    }

    r->count--;

    if (r->count || r->blocked)
    {
        return;
    }

#if (NGX_HTTP_V2)
    if (r->stream)
    {
        ngx_http_v2_close_stream(r->stream, rc);
        return;
    }
#endif

    ngx_http_free_request(r, rc);
    ngx_http_close_connection(c);
}


void
ngx_http_free_request(ngx_http_request_t *r, ngx_int_t rc)
{
    ngx_log_t                *log;
    ngx_pool_t               *pool;
    struct linger             linger;
    ngx_http_cleanup_t       *cln;
    ngx_http_log_ctx_t       *ctx;
    ngx_http_core_loc_conf_t *clcf;

    log = r->connection->log;

    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, log, 0, "http close request");

    if (r->pool == NULL)
    {
        ngx_log_error(NGX_LOG_ALERT, log, 0, "http request already closed");
        return;
    }

    cln        = r->cleanup;
    r->cleanup = NULL;

    while (cln)
    {
        if (cln->handler)
        {
            cln->handler(cln->data);
        }

        cln = cln->next;
    }

#if (NGX_STAT_STUB)

    if (r->stat_reading)
    {
        (void)ngx_atomic_fetch_add(ngx_stat_reading, -1);
    }

    if (r->stat_writing)
    {
        (void)ngx_atomic_fetch_add(ngx_stat_writing, -1);
    }

#endif

    if (rc > 0 && (r->headers_out.status == 0 || r->connection->sent == 0))
    {
        r->headers_out.status = rc;
    }

    if (!r->logged)
    {
        log->action = "logging request";

        ngx_http_log_request(r);
    }

    log->action = "closing request";

    if (r->connection->timedout)
    {
        clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

        if (clcf->reset_timedout_connection)
        {
            linger.l_onoff  = 1;
            linger.l_linger = 0;

            if (setsockopt(r->connection->fd, SOL_SOCKET, SO_LINGER,
                           (const void *)&linger, sizeof(struct linger))
                == -1)
            {
                ngx_log_error(NGX_LOG_ALERT, log, ngx_socket_errno,
                              "setsockopt(SO_LINGER) failed");
            }
        }
    }

    /* the various request strings were allocated from r->pool */
    ctx          = log->data;
    ctx->request = NULL;

    r->request_line.len = 0;

    r->connection->destroyed = 1;

    /*
     * Setting r->pool to NULL will increase probability to catch double close
     * of request since the request object is allocated from its own pool.
     */

    pool    = r->pool;
    r->pool = NULL;

    ngx_destroy_pool(pool);
}


static void
ngx_http_log_request(ngx_http_request_t *r)
{
    ngx_uint_t                 i, n;
    ngx_http_handler_pt       *log_handler;
    ngx_http_core_main_conf_t *cmcf;

    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);

    log_handler = cmcf->phases[NGX_HTTP_LOG_PHASE].handlers.elts;
    n           = cmcf->phases[NGX_HTTP_LOG_PHASE].handlers.nelts;

    for (i = 0; i < n; i++)
    {
        log_handler[i](r);
    }
}


void
ngx_http_close_connection(ngx_connection_t *c)
{
    ngx_pool_t *pool;

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "close http connection: %d",
                   c->fd);

#if (NGX_HTTP_SSL)

    if (c->ssl)
    {
        if (ngx_ssl_shutdown(c) == NGX_AGAIN)
        {
            c->ssl->handler = ngx_http_close_connection;
            return;
        }
    }

#endif

#if (NGX_STAT_STUB)
    (void)ngx_atomic_fetch_add(ngx_stat_active, -1);
#endif

    c->destroyed = 1;

    pool = c->pool;

    ngx_close_connection(c);

    ngx_destroy_pool(pool);
}


static u_char *
ngx_http_log_error(ngx_log_t *log, u_char *buf, size_t len)
{
    u_char             *p;
    ngx_http_request_t *r;
    ngx_http_log_ctx_t *ctx;

    if (log->action)
    {
        p = ngx_snprintf(buf, len, " while %s", log->action);
        len -= p - buf;
        buf = p;
    }

    ctx = log->data;

    p = ngx_snprintf(buf, len, ", client: %V", &ctx->connection->addr_text);
    len -= p - buf;

    r = ctx->request;

    if (r)
    {
        return r->log_handler(r, ctx->current_request, p, len);
    }
    else
    {
        p = ngx_snprintf(p, len, ", server: %V",
                         &ctx->connection->listening->addr_text);
    }

    return p;
}


static u_char *
ngx_http_log_error_handler(ngx_http_request_t *r, ngx_http_request_t *sr,
                           u_char *buf, size_t len)
{
    char                     *uri_separator;
    u_char                   *p;
    ngx_http_upstream_t      *u;
    ngx_http_core_srv_conf_t *cscf;

    cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

    p = ngx_snprintf(buf, len, ", server: %V", &cscf->server_name);
    len -= p - buf;
    buf = p;

    if (r->request_line.data == NULL && r->request_start)
    {
        for (p = r->request_start; p < r->header_in->last; p++)
        {
            if (*p == CR || *p == LF)
            {
                break;
            }
        }

        r->request_line.len  = p - r->request_start;
        r->request_line.data = r->request_start;
    }

    if (r->request_line.len)
    {
        p = ngx_snprintf(buf, len, ", request: \"%V\"", &r->request_line);
        len -= p - buf;
        buf = p;
    }

    if (r != sr)
    {
        p = ngx_snprintf(buf, len, ", subrequest: \"%V\"", &sr->uri);
        len -= p - buf;
        buf = p;
    }

    u = sr->upstream;

    if (u && u->peer.name)
    {
        uri_separator = "";

#if (NGX_HAVE_UNIX_DOMAIN)
        if (u->peer.sockaddr && u->peer.sockaddr->sa_family == AF_UNIX)
        {
            uri_separator = ":";
        }
#endif

        p = ngx_snprintf(buf, len, ", upstream: \"%V%V%s%V\"", &u->schema,
                         u->peer.name, uri_separator, &u->uri);
        len -= p - buf;
        buf = p;
    }

    if (r->headers_in.host)
    {
        p = ngx_snprintf(buf, len, ", host: \"%V\"",
                         &r->headers_in.host->value);
        len -= p - buf;
        buf = p;
    }

    if (r->headers_in.referer)
    {
        p   = ngx_snprintf(buf, len, ", referrer: \"%V\"",
                           &r->headers_in.referer->value);
        buf = p;
    }

    return buf;
}
